A. J. Downing, Esq

Tour learned correspondent, Mr. Townley, in an essay on the "Conditions required for the growth of Parasitic Fungi," published in the Horticulturist for July, uses the following language: - "I may be permitted to say that the evidence of apple trees and other plants seems to me to afford substantial grounds for coinciding with the views advanced by Andrew Knight, that each plant propagated by extension, that is, by buds, cuttings, layers, or roots, instead of seeds, has a limited duration - that it cannot, by any known means, be continued equally healthy and vigorous forever; but that sooner or later the progeny will gradually decline in vigor, become unhealthy and unproductive, not suited to the purposes of the cultivator, and consequently extinct."

The evidence of apple trees and other plants! Well, that is coming to the point. As Mr. Townley is in possession of such evidence on the subject as affords him substantial grounds for coinciding in those views, I hope he will be kind enough to lay it before the readers of the Horticulturist, that each one may decide for himself. Some people, believe easier than others. Give us the facts, and let each one draw his own conclusions.

Again, (on page 320,) speaking of restoring the potato by seedlings, he says - "It is equally vain to expect, as many have done, that the vigor of the plant can be restored by one generation of seedlings. The progeny of unhealthy and degenerate parents cannot reasonably be expected to be perfectly healthy and hardy."

He first condemns propagation by extension, in comparison with seeds, and then condemns the seedlings too. His hobby evidently trips a little here; - I like to see so bold a rider mounted on a sure-footed nag.

Now, if the evidence shall prove conclusively that trees and plants propagated by extension, do produce degenerate fruit from that very cause, and that alone; that the seeds also partake of the degeneracy, and can only be restored through many generations, if at all; then we may prepare to shut our mouths against good apples and potatoes, for a long time to come.

Seedling apples must be resorted to, in order to restore the fruit to its pristine purity, says our new philosophy. We have the Northern Spy, the Melon, the Mother, the Baldwin, the Jeffries, and many others. Now we want to see the evidence that the seeds from which those new varieties were produced, were not of the fruit of some of the old "degenerate" varieties. If this cannot be produced, we may have a long road before us to travel before reaching the summit of perfect fruit, by a wild-goose chase of seedlings.

Our natural fruit extension; therefore, according to this new philosophy, we must have nothing to do with them.

In conclusion, Mr. Editor, I would advise your readers to propagate good old varieties of the apple by extension, as they used to do - get fat on the fruit, and not get frightened before they are hurt. Tours, etc. A. Marshall.